Sorption of strontium

Small TD, Warren LA, Roden EE, Ferris FG (1999) Sorption of strontium by bacteria, Fe(III) oxide, and bacteria-Fe(III) oxide composites. Environ Sci Technol 33 4465-4470... 

Sorption on oxides and hydrous oxides has been extensively studied both experimentally and theoretically. In order to define an ideal oxide or hydrous oxide exchanger, we will rely on experiments with well-defined sorbents such as chromatographic alumina (1-4). Briefly, the adsorption characteristics of oxides and hydrous oxides are (1) At high pH, they act as cation exchangers but with less sensitivity to the total salt concentration than clay minerals. This behavior is illustrated in Figure 2, where sorption of strontium on alumina is shown. 

Sorption Prediction Equations. Equations predicting radioelement distribution coefficients, K s, as arithmetic functions of component concentrations were obtained for sorption of strontium, neptunium, plutonium, and americium on two Hanford sediments. These equations, presented in Table VH and derived from statistical fits of Box-Behnken experimental designs, were generated for strontium in terms of sodium ion, HEDTA, and EDTA concentrations. Prediction equations for neptunium and plutonium sorption were derived from NaOH, NaA102, HEDTA, and EDTA concentrations. Americium sorption prediction equations were based on NaOH, HEDTA, and EDTA concentrations. 

The solubility results were reflected in the sorption behaviors observed for the five radioelements. Sorption of strontium and americium was decreased by HEDTA and EDTA. Cobalt sorption also decreased in the presence of HEDTA. Sorption of both cobalt and strontium was decreased by increasing sodium ion concentration in the HLW due to competition of the cations for sorption sites. 

Missana, T., M. Garcia-Gutierrez, and U. Alonso. 2008. Sorption of strontium onto illite/ smectite mixed clays. Phys. Chem. Earth, Parts A/B/C 33 S156-S162. 

Nemes, Z., N. M. Nagy, A. Komlosi, and J. Konya. 2006. The effect of mineral composition on the sorption of strontium ion on geological formations. Appl. Clay Sci. 32 172-178. 

DelDebbioJA. 1991. Sorption of strontium, selenium, and mercury in soil. Radiochimica Acto 52-53(ptl) 181-186. 

Erdal, B.R. Aguilar, R.D. Bayhurst, B.P. Daniels, W.R. Duffy, C.J. Lawrence, F.O. Maestas, S. Oliver, P.Q. Wolfsberg, K. "Sorption-Desorption Studies on Granite. I. Initial Studies of Strontium, Technetium, Cesium, Barium, Cerium, Europium, Uranium, Plutonium, and Americium", in "Proceedings of the Task 4 Waste Isolation Safety Assessment Program Second Contractor Information Meeting", Vol. II, Report PNL-SA-7352, Battelle Pacific Northwest Laboratory, 1978, pp. 7-67. 

N. Carroll, S.A. (2000) X-ray absorption spectroscopy of strontium coordination. II Sorption and precipitation at kaolinite, amorphous silica and goethite surfaces. J. Coll. 

Trivedi, P. Axe, L. (1999) A comparison of strontium sorption to hydrous aluminum, iron, and manganese oxides. J. Coll. Interf. Sd. 218 554-563... 

Therefore, the preliminary investigation described herein examined several aspects of the behavior of the equilibrium distribution coefficients for the sorption of rubidium, cesium, strontium, barium, silver, cadmium, cerium, promethium, europium, and gadolinium from aqueous sodium chloride solutions. These solutions initially contained one and only one of the nuclides of interest. For the nuclides selected, values of Kp were then... 

Variables found to be significant for sorption of cesium, strontium, technetium, selenium, neptunium, plutonium, americium, and radium on sandstone and tuff at 23°C are given in Table VII. They are ranked in order of significance where more than one variable was found to be significant. The ( + ) and (-) signs indicate whether sorption is increased or decreased. 

Effects of Hanford High-Level Waste Components on the Solubility and Sorption of Cobalt, Strontium, Neptunium, Plutonium, and Americium... 

Chemical components in the waste solutions potentially could affect radioelement solubility and sorption reactions, and thus enhance or reduce radionuclide transport. The effects of 12 chemical components on the solubility and sorption of cobalt, strontium, neptunium, plutonium, and americium were studied to... 

Strontium sorption behavior was consistent with the strontium solubility behavior described earlier. Both HEDTA and EDTA significantly decreased strontium sorption through formation of poorly sorbed anionic complexes (4). Close inspection of the test data suggested that increased sodium ion concentration might have led to decreased strontium sorption. The competition of strontium with sodium for sorption sites had been observed previously for Hanford sediments (13). 

As seen in Table 3.9, the difference between the experimental and calculated values is below 0.033 in the case of the Egyhazaskeszo, Istenmezeje (black and yellow), Mad Ujhegy, and Sajobabony samples. This value is in the range of the deviation of the determination of the mineral composition and the sorption experiments (5%-10%). So, the model, similar to cesium ion, fairly well describes the relation of the mineral composition and adsorbed quantity of strontium ion on different rocks. The deviation is higher in the case of the two samples (Kuzmice, Muiden), the main component of which is cristobalite, and it can be explained with the presence of a gel phase (Chapter 1, Section 1.3.6.1). 

The kinetic properties of strontium sorption on clinoptilolite from both model solutions and natural seawater have been investigated in detail [252, 253]. These properties are determined by diffusion in both the zeolite microcrystals and the intercrystalline porous space [252]. Methods for determining the characteristic size of microcrystals by an ion-exchange technique are given in [253]. Such estimates provided a determination of their size-based contribution to the diffusion process. 

Marageh M.G., Husain S.W., and Khanchi A.R., Selective Sorption of Radioactive Cesium and Strontium on Staimic Molybdophosphate Ion Exchanger , Applied Radiation and Isotopes SO... 

Liang T., Hsu C., Sorption of Cesium and Strontium on Natural Mordenite , Radiochimica Acta. 61(1993) 105. 

Ion-exchange models are commonly used to describe radionuclide sorption onto the fixed-charged sites of materials like clays. Ion exchange will be strongly affected by competition with monovalent and divalent ions such as Na" " and Ca, whereas it will be less dependent on pH over the compositional ranges common for natural waters. Many studies of strontium and caesium sorption by aluminosilicates (e.g., Wahlberg and Fishman, 1962 Tamura, 1972) have been carried out within the framework of ion-exchange theory. Early mechanistic smdies... 

Ohnuki, T. (1994). Sorption characteristics of strontium on sandy soils and their components. Radiochim. Acta 64, 237—245. 

Hofmann, A. et al., Sorption kinetics of strontium in porous hydrous ferric oxide aggregates II. Comparison of experimental results and model predictions, J. Colloid Interf. Sci., 283, 29, 2005. 

Smiciklas, LD. et al.. The point of zero charge and sorption of cadmium(ll) and strontium(II) ions on synthetic hydroxyapatite, Separ. Purif. Technol., 18, 185, 2000. Newcombe, G., Hayes, R., and Drikas. M., Granular activated carbon Importance of surface properties in the adsorption of naturally occurring organics. Colloids Surf. A, 78, 65, 1993. 

---